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Vdc in ripple factor

Vdc = Vac RMS x SQRT2/(1+1/2frc) ac, rectifier, capacitor filter, load resistor. f is ripple frequency after rectifier, c is Farads, r is OHMS.
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Power supply overload protection work around

I need to switch on a contactor that uses around 3.2A inrush current for around 20ms... ...the power supply breaks down the output voltage around 3.1A ... at 3.1A, the output voltage of the power ...
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Power supply overload protection work around

First, you’ll need a representative SPICE model for the contractor coil. Measure the inductance and series resistance of the contractor coil – using an LCR meter, as it’ll do both at once. Then ...
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Power supply overload protection work around

I'm not sure you'd actually want to do this... adding a C in parallel to the relay coil will form a resonant tank circuit. When power is removed, the the 3.1A stored in the relay will start ...
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Electret microphone to speaker noise

Of course you have acoustical feedback howling. The mic can hear the speaker and causes sounds to go around and around. Out the speaker and into the mic, amplified then out the speaker and into the ...
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Can you cascade simple wideband bandpass active filters?

Cascading means convolution, and repeated convolution converges towards a Gaussian, which means a bell-shaped curve, not a flat plateau. it doesn't matter how far apart the edges are, that wil be the ...
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Can you cascade simple wideband bandpass active filters?

The cascaded 1st order LP and HP can have separate breakpoints and thus a wide plateau at some fixed gain at Av=R2/R1, if the breakpoints for LP are < HP. While a 2nd order Bandpass, Multiple ...
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Making a voltage range filter (or a voltage bandpass filter)

this can't be done with just passive components -- you'll need some transistors and/or comparators. With comparators, set one up to detect if VIN > 1 V, the other if VIN < 2 V. Then AND the 2 ...
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Bandpass filter doesn't work when implementing PCB

Each track has both inductance, capacitance and resistance and thus a characteristic impedance from Z^2=L/C I believe you only have trace inductance. That will not work. There are ways that do work. I ...
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Help Understanding Opamp Topology (Infinite Gain Multiple feedback with Resistor to Gnd?)

Antonio shows that varying R14 can shift resonant frequency. Look closely, resonant bandwidth changes. As frequency drops with higher values of R14, Q is lower. If you want frequency to remain ...
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Help Understanding Opamp Topology (Infinite Gain Multiple feedback with Resistor to Gnd?)

R14 (my R2) is very useful. Displace the center frequency "bandpass" filter. Updated info: One should see "analog filters handbook chapter8" from Analog Devices, page 8.76 fig 8....
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Digital Signal Processing vs. Analog Signal Processing for 100kHz DAQ project

OVersampling with decimation helps to reduce the order of the "brick wall" filter for Nyquist aliasing noise to be rejected where the dynamic range and ratio of oversampling determine order ...
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Digital Signal Processing vs. Analog Signal Processing for 100kHz DAQ project

Do we really need an analog filter if the signal is to be converted to digital? First thing: you need an aliasing filter before the ADC. This may already be done on the DAQ board, so check that. As ...
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Digital Signal Processing vs. Analog Signal Processing for 100kHz DAQ project

ADCs usually need an anti-aliasing filter, otherwise frequencies above Fs/2 will alias to frequencies below Fs/2. For example if your sampling frequency is 48kHz and there is no anti-alias filter, a ...
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Digital Signal Processing vs. Analog Signal Processing for 100kHz DAQ project

In two pictures (made using octave) a 1 kHz signal sampled at 1100 sps: and at 1200 sps: How could digital processing distinguish those from (respectively) 100 Hz and 200 Hz signals? Aliasing must ...
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RC filters in JFET negative feedback

JFET filter can be used with varying your C9 and C10. Here's what happens ... with "no load" ...
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How to simulate an AC line filter in LT Spice

You have to define LINK FACTOR AS K1 L1 L2 1
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